I used both Milton and an electric steam steriliser (I combination breast/formula fed). My steriliser fit 6 bottles (including the actual bottle itself and the teats) and didn't fit the lids in at the same time. Since I was using 6 bottles a day, it suited me perfectly to wash up one load a day, then put the bottles/teats in the steriliser and the lids in the Milton solution. That way, everything was cleaned and sterilised, all in one go, and ready to start the next day.